Field of the Invention
The present application relates to an orthodontic correction technology; and in particular to a removable orthodontic correction device.
Description of the Related Art
Misaligned teeth can adversely affect a person's dental aesthetics, functions, and health. The goal of orthodontic correction is to bring the teeth into proper alignment by using appliances which exert mechanical forces to move the teeth to positions or orientations where the dental functions and aesthetics are improved.
Dental protrusion is a common condition requiring orthodontic treatment. Dentoalveolar protrusion of the maxillary or both the maxillary and mandibular (bimaxillary) anterior teeth results in a convex facial profile. The current treatment for maxillary or bimaxillary protrusion is to extract the first or second premolars, thereby creating a space for anterior teeth retraction. The space closure step is a challenge, calling for an effective mechanism to achieve smooth retraction of the anterior teeth. To prevent the excessive inclination of the anterior teeth due to retraction, simultaneous intrusion of the anterior teeth is required.
FIG. 1 is a schematic view illustrating a prior art orthodontic correction device being worn on the maxillary dental arch of a patient to achieve space closure in the treatment of maxillary protrusion. As shown in FIG. 1, the orthodontic correction device includes several brackets 20 fixed on the anterior teeth (e.g. the incisors 10, lateral incisors 11, canines 12, and first premolars 13) of the maxillary dental arch, several brackets 21 fixed on the posterior teeth (e.g. the first molars 14) of the maxillary dental arch, a lingual archwire 22 engaging the brackets 20 and 21, several hooks 23 formed as part of the brackets 20, several mini-screw implants 24 fixed on the palate of the maxilla M, and several elastic members 25 coupling the hooks 23 to the mini-screw implants 24.
In this case, the extraction of the second premolars creates the correction spaces S formed between the first premolars 13 and the first molars 14. The mini-screw implants 24 fixed to the palate of the maxilla M act as anchorage, and the elastic members 25 exert elastic traction force on the hooks 23 to achieve retraction and intrusion of the anterior teeth (as the arrow indicates in FIG. 1), thereby closing the correction spaces S (i.e. gaps between the anterior teeth and the posterior teeth).
However, while using the orthodontic correction device described above, the mini-screws implants 24 are implanted in the palate of the maxilla M. This is an invasive procedure which can cause local inflammation, and the presence of the implants can restrict tongue motion and cause discomfort to the patient during space closure. Also, the brackets 20 and 21 are bonded to the teeth, and consequently the lingual archwire 22 and the hooks 23 are also long-term fixtures, which is an inconvenience for the patient when eating or brushing teeth. In addition, debonding of brackets and the removal of adhesive or resin debris from the enamel surface can cause damage to the tooth enamel.